No, not a typo. . . .

All during the 80's and 90's I avoided internal cable routing (brake cables)
coz I thought:
1) the aero advantage ain't all its cracked up to be
2) sidepull brakes of the day were dicey enough,
why mess with weird lever configurations
3) it's a fad, this too will pass.

so, fast forward 20 years and I have a new(old) bike with
you guessed it Infernal cable routing.
The brakes are Modolo Professional (not sure if the levers are Master pro's).
For the initial build I just threw parts at the bike to get it out the door
for a ride or two, now I'm ready to build it right.
I have to admit the cables exiting the top of the lever
and looping over the bars and disappearing into the
top tube looks dumb (wrong?).
So my question (you knew there had to be one):
How do I route the cables through the brake lever body for
the aero routing?

thanks in advance,
Marty